Interest in the salivary indices of the individual psychosomatic stress response has focused on various components of the salivary proteome including α-amylase, cortisol, dehydroepiandrosterone-sulphate (DHEA-S), testosterone, chromogranin A, and secretory immunoglobulin A (SIgA). The nonintrusive nature of saliva collection and the minimal processing required renders saliva an attractive alternate to blood and urine. The ease of saliva collection greatly facilitates subject compliance and allows repeat, self-administered sampling in naturalistic settings without the need for specialized personnel or equipment. Correspondingly, saliva is increasingly utilized in psychobiological studies. Recent developments in technology platforms allow near real-time detection and quantification of salivary stress response indicators. This review focuses on the current status of these developments in salivary biosensing technology and future technological advances that will render biomarkers more field-practical and accessible to end-users in a cost-effective manner. The maturation salivary biosensor prototypes into commercial devices will happen as the functionality, performance and production costs improve. In the long term, the growing convergence of proteomic and genomic profiling, biosensing technology and bioinformatics will allow salivary biomarker-based strategies to become ingrained in experimental studies and eventually, lead to better risk assessment, diagnosis and a patient-centric management of stress-related diseases.

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Electroreduction of optically active (S)- and (R)-N-(3-butenyl)(or (R)-N-benzyl)-2-acetylpyrrolidines (1a) and (1b) (or (2b)) were carried out in N,N-dimethylformamide containing Et₄NOTs as a supporting electrolyte, which brought about highly stereo- and regioselective intramolecular cyclization with diastereoselective asymmetric induction to give the corresponding (4S,5R,6S)- and (4R,5S,6R)-cis-4,5-dimethyl-1-azabicyclo[4.3.0]nonan-5-ols (3a) and (3b) (or (8R,9S,10R)-9-methyl-1-azatricycro[8.3.0^1,10.0^3,8]tridecane-9-ol-3,6-diene (4b)) in 66% and 49% (or 31%) yields, respectively.

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An ammonia gas sensor was fabricated using Al³⁺ ion conducting (Al_0.2Zr_0.8)_20/19Nb(PO₄)₃ solid electrolyte with NH₄⁺-β-gallate (NH₄⁺-Ga₁₁O₁₇) as the auxiliary sensing electrode and its performance in humid atmosphere was investigated. The sensor exhibited advanced sensing performance than previously reported NH₃ gas sensors with a continuous, quantitative and reproducible response that obeys the theoretical Nernst relationship even in a highly humidified atmosphere containing 4.2 vol % H₂O at 230°C. Therefore, the proposed sensor with NH₄⁺-β-gallate auxiliary sensing electrode is expected to be a suitable candidate for application as a practical on-site NH₃ gas detecting tool.

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Additive behaviors of several bis (trifluoromethylsulfonyl) amide-based phosphonium salts in an organic electrolyte used for lithium secondary batteries are reported. Electrolytic properties of a lithium hexafluorophosphatebased organic electrolyte mixed with the phosphonium salts were examined. It was found that the mixed electrolytes containing the phosphonium salts showed lower conductivities and higher viscosities than the organic electrolyte. However, in the case of the mixed phosphonium electrolytes based on asymmetrical cations, the charge-discharge cyclabilities of the lithium battery cells were superior to that of the cell containing the organic electrolyte. Furthermore, the thermal stability of LiCoO₂ cathodes charged in the mixed phosphonium electrolytes was considerably improved. These results suggest that the phosphonium salts are regarded as effective electrolyte additives for lithium secondary batteries.

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Manganese oxide thin films are deposited on graphite foils by a dry process, one step reactive radio frequency (RF) magnetron sputtering with different volume flow rates of oxygen and sputtering time. Maximum mass specific capacitance of 320.26 F g⁻¹ is obtained in 0.5 M LiCl as well as with optimum sputtering conditions [volume flow rate of oxygen=10 sccm (cm³ min⁻¹) and sputtering time=60 min], and this demonstrates its good mass specific capacitance at a sweep rate of 100 mV s⁻¹. Furthermore, the mass specific capacitance and the geometric specific capacitance increase at lower volume flow rates of oxygen, but decrease at higher volume flow rates of oxygen. Moreover, the electrochemical stability of the electrode increases with increasing sputtering time.

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A performance at high temperature of all-solid-state battery with LiMn₂O₄/honeycomb Li_0.35La_0.55TiO₃/Li₄Mn₅O₁₂ configuration was examined. The charge and discharge capacities increased with test temperature until 100°C by favorable Li ion conductivity of electrolyte. At 120°C, deterioration of the performance was observed due to instability of electrode material. It is found that the all-solid-state battery can be operated until 100°C. The discharge capacity at 100°C was 74 µA h cm⁻² at current density of 100 µA cm⁻².

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LiMnPO₄ has been much attention for cathode material of next generation lithium ion battery. The most serious problem of this cathode material is intrinsic low electronic conductivity. In this study, Mg doping to carbon-coated LiMnPO₄ prepared by hydrothermal route was performed to improve the electronic conductivity. The Mg doping did not affect on particle size and shape of LiMnPO₄ as well as formation of surface carbon layer. In charge and discharge test, improvement of performance of LiMnPO₄ due to the Mg doping was clearly demonstrated. The improvement is attributed to superior electronic conductivity due to the Mg doping.

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